This application claims the priority of German patent application 199 30 399.1, filed Jul. 1, 1999, the disclosure of which is expressly incorporated herein by reference thereto.
The present invention relates to a battery container for a plurality of particularly cylindrical accumulator elements as well as to a motor vehicle equipped with such a battery container.
From German Patent Documents DE 41 16 253 C1 and DE 195 04 687 C1, battery containers are known which are normally fastened directly in the carrying floor structure of a motor vehicle body. A plurality of electrochemical energy accumulators, in the following called accumulator elements, are arranged in battery containers of this type. The accumulator elements may either be individual accumulator cells or several accumulator cells which are fixedly connected in series with one another to form a so-called accumulator module. From a German patent application with the File Number 198 48 646.4, which was filed by the same applicant but has not yet been published, it is known to provide an accumulator element holding device in a battery container of the above-mentioned type, which holding device comprises devices for the form-locking fixing of the accumulator cells. These devices are applied laterally and at the end side to the accumulator elements.
When designing battery containers of the above-mentioned type, it is a general goal to provide a self-supporting structure which is suitable for a free arrangement in a recess of a vehicle body, which has a weight that is as low as possible and which can accommodate a maximal number of accumulator elements while its own weight is as low as possible. Furthermore, the diversion of the extensive heat development must be ensured which occurs during the charging of the accumulator elements as well as during their power output.
Based on the above, it is an object of the invention to provide a self-supporting battery container of the above-mentioned type which ensures a defined position of the accumulator elements held therein as well as an effective moderating of the temperature.
For achieving this object, the present invention provides a battery container for a plurality particularly of cylindrical accumulator elements which are arranged parallel to one another in rows and/or layers essentially horizontally, each having at least one first fixing element arranged on a bottom plate and a cover plate of the battery container, which fixing element extends transversely to the longitudinal axes of the accumulator elements and, with a form-locking action, fixes and supports the accumulator elements in the horizontal and the vertical direction.
Accordingly, the accumulator elements are arranged in the battery container parallel to one another in rows and/or layers essentially horizontally, thus in a lying position. For holding the accumulator elements, at least one first fixing element respectively is arranged on a bottom plate and a cover plate of the battery container, which fixing element extends transversely to the longitudinal axes of the accumulator elements and which, with a form-locking action, fixes and supports the accumulator elements in a horizontal and vertical direction. By means of the fixing elements provided according to the invention, the accumulator elements, while being arranged horizontally, are in each case fixed and supported in the horizontal and in the vertical direction, whereby the accumulator elements are protected from bending as well as held immovably in the horizontal direction therefore, while the distances provided between individual accumulator elements arranged parallel to one another are maintained, which distances are important for the circulation of the cooling fluid.
Because of the arrangement of the fixing elements essentially transversely to the longitudinal axes of the accumulator elements, the accumulator elements are not supported along their outer jacket but only at individual points, whereby the moderating of the temperature, thus the removal of heat developed in the accumulator elements, is facilitated. According to the invention, the support takes place by at least one first fixing element arranged on the bottom plate and on a cover plate of the battery container. In the case of a layer-type arrangement of the accumulator elements, which particularly takes place in a coplanar arrangement of the longitudinal axes of the stacked accumulator elements, according to an advantageous further development of the invention, additional fixing elements are arranged between two layers of accumulator elements respectively, which additional fixing elements also extend transversely to the longitudinal axes of the accumulator elements and fix and support these in the horizontal and vertical direction while acting upon them in a form-locking manner. In particular, the first and additional fixing elements are each arranged above one another, whereby a particularly good stiffness of the arrangement is achieved.
As a further development of the invention, the fixing elements are arranged in the area of at least one longitudinal end of the accumulator elements. If the length of the battery container corresponds to the length of an accumulator element, the fixing elements are preferably arranged at each longitudinal end of the accumulator elements, so that each accumulator element is fixed and supported at its two longitudinal ends in the horizontal and vertical direction. As a function of the requirements, particularly according to the length of the accumulator elements, additional holders may be provided in order to prevent a bending of the accumulator elements. Holders of this type will be described in detail in the following.
If two or more accumulator elements mutually connected in the longitudinal direction are arranged in the battery container, the fixing elements are preferably arranged only between longitudinal ends of accumulator elements which are in a longitudinal connection with one another. If, for example, for each row, two accumulator elements are arranged in the battery container coaxially connected with one another at their poles by means of a suitable pole connector, one fixing element respectively is provided for their fixing and support between each layer as well as on the bottom plate and the cover plate, which fixing element extends transversely to the longitudinal direction of the accumulator elements approximately in the center of the battery container and fixes and supports the accumulator elements in the area of the pole connection in the horizontal and vertical direction.
As an advantageous further development of the invention, the bottom plate and the cover plate and the fixing elements have slots for guiding incoming air and outgoing air or cooling fluid. This measure ensures a suitable moderating of the temperature of the accumulator elements arranged in the battery container.
As a particularly advantageous embodiment of the invention, the fixing elements have pockets for the form-locking accommodation of the longitudinal ends of the accumulator elements. As a result, a particularly good fixing and support of the accumulator elements is achieved in the horizontal and vertical direction. In particular, the pockets are divided-circle-shaped recesses in the surface of the fixing elements, whose radius corresponds essentially to the radius of the essentially cylindrical accumulator elements and whose center is situated on the longitudinal axis of the accumulator elements placed therein. At the end side of the longitudinal end of the accumulator element, the pocket forms an essentially perpendicularly extending stop face, so that the accumulator element is fixed in the longitudinal direction. It was found to be particularly advantageous to lengthen the divided-circle-shaped recesses in the fixing element at least partially in a web-type manner vertically upward in order to provide the accumulator elements placed in the pocket with a hold which is as good as possible.
As an advantageous further development of the invention, the slots for guiding the cooling fluid are assigned to the pockets such that poles situated at the longitudinal ends of the accumulator elements are acted upon by a cooling fluid flow guided through the slots. This can, for example, be achieved in that, viewed in the longitudinal direction of the accumulator element, the slots are formed behind the stop face of the pocket and/or between adjacent pockets, thus diagonally next to or partially below the point at which the pole of the accumulator element comes to be situated when the accumulator element is inserted.
In order to design the entire arrangement for holding the accumulator elements to be as light as possible, the fixing elements advantageously consist of plastic, particularly of polycarbonate.
For increasing the stiffness, the fixing elements preferably have a sandwich structure.
As an advantageous embodiment of the invention, at least one spacer is provided which extends essentially parallel to the fixing elements, which prevents a bending of the accumulator elements and defines a gap between parallel accumulator elements. As a result of this measure, the number of fixing elements can be reduced to the minimum required for fixing and supporting the accumulator elements, while for the support of the accumulator elements at an opposite end or in their center, for preventing a bending and for defining a gap between individual accumulator elements, through which cooling fluid can circulate, smaller and thus lighter spacers are used which absorb only vertical forces and optionally lateral forces. However, horizontal forces in the longitudinal direction of the accumulator elements do not have to be absorbed by these spacers.
Like the fixing elements, the spacers advantageously consist of plastic, particularly of polycarbonate, and, in addition, have a sandwich structure for increasing the stiffness.
In another embodiment of the invention, the fixing elements are arranged between longitudinal ends of accumulator elements which are in a transverse connection with one another. In the case of this variant, the battery container is filled with accumulator elements which are arranged side-by-side and behind one another in rows and layers, however, a connection of individual accumulator elements not taking place between accumulator elements arranged behind one another in the longitudinal direction but between adjacent accumulator elements which are situated side-by-side. In this variant, the fixing elements preferably have at least one row of recesses for the form-locking receiving of the accumulator elements as well as pole guiding grooves assigned to one recess respectively, for guiding the pole of an accumulator element inserted in the corresponding recess. By means of such a further development of the fixing elements, a positional securing of the accumulator elements is ensured at their circumference as well as in the area of the poles. A separate guiding of the poles also facilitates the insulation with respect to the accumulator elements which are situated behind in the longitudinal direction.
In a particularly advantageous feature of preferred embodiments of the invention, the grooves are formed in a transverse strip arranged behind the recesses in the longitudinal direction of the accumulator elements to be inserted. As a result, a particularly compact construction is permitted, particularly if the transverse strip is constructed in one piece with the fixing element.
It was found to be particularly advantageous to construct the transverse strips to be lower than supporting webs arranged between the recesses, whereby, when individual fixing elements are placed upon one another, a transverse guiding is generated for pole connectors.
As another advantageous feature of preferred embodiments of the invention, the grooves are also used for guiding cooling fluid in that they have a continuous construction and the groove walls extend in the transverse direction spaced away from poles placed therein.
For an improved insulation between accumulator elements which follow one another in the longitudinal direction, insulating plates are advantageously provided at least in the area of the pole guiding grooves between fixing elements which follow one another in the longitudinal direction of the accumulator elements.
The invention also relates to a motor vehicle having a self-supporting battery container according to the invention which is preferably arranged in a suitable opening of the vehicle body or the chassis of the motor vehicle.
Further advantages and developments of the invention are indicated in the description and in the attached drawing.
It is understood that the above-mentioned characteristics, which will be explained in the following, can be used not only in the respectively indicated combination but also in other combinations or alone without leaving the scope of the present invention.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.